The half life of this radioisotope is 12 hours.
<u>Explanation:</u>
The length of time it requires to break down for an initial half amount or the amount of time taken to transform half of a reactant into product. Half of a particular sample took the time to experience radioactive decay. The time it would take to degrade radioactively into another component or nuclide for half of the atoms of an unstable element or nuclide.
If 1/16 of the sample remains it predicts that there were 4 half-life periods then 16 = 2⁴
4 half-life periods = 48 hours / 4
half-life period = 12 hours.
Answer:
B. 4 ham slices
Explanation:
A chemical reaction involves one or more substances known as reactants combining chemically to give one or more substances known as products.
Reactants in chemical reactions combine in definite mole or mass ratios to give products. Therefore, when one substance is present in excess of what is required to combine with another to form products, that substance is known as the excess reagent. The other substance which is present in a smaller amount and which when used up, the reaction stops is known as the limiting reagent.
From the illustration of the sandwiches in the question, the recipe for one sandwich represents the chemical equation of a reaction. The equation form is given below:
2 cheese slices + 1 ham slice + 2 bread slices ---> 1 sandwich
The ratio of the reactant is 2 : 1 : 2
From the available ingredients, 12 cheese slices, 10 ham slices, 12 bread slices.
12 cheese slices will require 6 ham slices and 12 bread slices to produce 6 sandwiches.
However, since there are 10 ham slices, 4 ham slices will be left over unused. This is the excess or leftover reactant.
Answer:
1. A. Thyroid Gland Function
B. detecting Blood Clots
C. Treating Cancer
2. An example would be how many are used as tracers for diagnostic purposes
3. Beneficial because it gives us ways to eleminate pests, by the sterile insect technique
Number three is kinda iffy a bit difficult to explain it may be explained better in your book.
Answer: permanent removal of hair by energy or heat
Explanation:
Atomic mass of Br = 79.904
<span>Now lets say y% is abundance of 79Br. </span>
<span>Then abundance of 81Br = (100 - y) </span>
<span>mass due to 79Br = 78.9183 * y/100 = 0.789183y
</span><span>mass due to 81Br = 80.9163 x (100 - y)/100 = 0.809163(100 - y) </span>
<span>Therfore</span>
<span>0.789183y+ 0.809163(100 - y) = 79.904 </span>
<span>0.789183y + 80.9163 - 0.809163y = 79.904 </span>
<span> - 0.01998y= 79.904 - 80.9163
= - 1.0123 </span>
<span>y = 1.0123/0.01998 = 50.67% </span>
<span> 79Br = 50.67% </span>
<span>now
81Br = 100 - 50.67 = 49.33%
hope this helps</span>
